1. Technical Field
The present invention relates to a power steering gear assembly. In particular, the present invention relates to an actuator assembly for a pressure relief valve in a fluid power assisted steering gear assembly.
2. Description of the Prior Art
Fluid power assisted steering gear assemblies for vehicles are known. One such steering gear assembly is disclosed in U.S. Pat. No. 4,773,303 and includes a piston which moves through a work stroke in a fluid chamber. The piston is connected through a pitman arm with the steerable wheels of the vehicle. The steerable wheels, at the end of their range of movement, engage steering stops on the vehicle.
The steering gear assembly disclosed in U.S. Pat. No. 4,773,303 includes a valve assembly movable with the piston in the fluid chamber. When the piston reaches a predetermined end-of-stroke position in the chamber, the valve assembly is actuated and relieves fluid pressure in the chamber. The end-of-stroke position of the piston is set so that pressure in the fluid chamber is relieved just prior to the steerable wheels engaging the steering stops on the vehicle. Relieving the pressure protects the power steering pump and other parts of the steering gear and steering linkage from damage.
The steering stops on a vehicle may sometimes be moved to provide a smaller range of movement of the steerable wheels of the vehicle. When this is done, it becomes necessary to adjust the steering gear assembly to provide for a shorter work stroke of the piston. The steering gear assembly of U.S. Pat. No. 4,773,303 must be removed from the vehicle and disassembled in order to accomplish this. It would be desirable to be able to reset the end-of-stroke position of the piston to provide for a shorter work stroke without disassembling the steering gear.